Temperatures had been high for the time of year and with short daylight hours Jon and Matt started climbing at 3.30am aiming to get to the shaded deep fault 650m up before the sun hit the face. The line, which rarely comes into condition, climbs narrow ice runnels, steep cascade ice and delicate/loose mixed ground up a deep fault line with vertical walls either side. The line controversially finishes about 60metres below the Tronchey ridge after the first ascent team found that the terrain above was un-climbable without the use of bolts. The amazing face and line is easily visible from Val Ferret in Italy.

Matt and Jon had planned to extend Plein Sud to the ridge then to the summit of the Grandes Jorasses, but soon realised why the first ascensionists made the decision to stop roughly a pitch below the ridge. They encountered sizable stacked loose blocks, and the risk of pulling rock off onto the belayer was not justifiable. Even by this point they had already trundled a significant volume of rocks. Disappointed at not being able to carry on to the summit of the Grandes Jorasses, they started abseiling at 2.30pm at which point they described the route below them as being "in total melt down", with streaming water completely stripping the line in places.

They reached their bivouac site at 5.30pm. "We were a little wet after playing in some waterfalls on the way down!" they commented.

Matt and Jon highly rated the climbing on this infrequently traveled face and said:

"This is one of those routes where conditions are rare and extending Plein Sud to the summit would take exceptional conditions, but the route as it stands still gives a fantastic outing and we would like to thank the first ascent team for providing such a great adventure in a beautiful setting – Sergio De Leo, Michel Coranotte, Marcello Sanguineti, Maro Appino."

Plein Sud was first climbed on the 22 May 2010, is 900m and Graded VI, WI4+/5R, M6+.